Editing Road train (section)

=== Australia ===
[[File:Australian road train headed by Volvo NH15.jpg|thumb|right|A four-trailer road train in the Australian outback with a [[Volvo Trucks|Volvo]] NH15 prime mover]]
The term ''road train'' is used in Australia and typically means a prime mover hauling two or more trailers, other than a B-double.<ref>{{cite web |url=https://www.nti.com.au/better-business-hub/blog/do-your-staff-know-an-a-from-b |title=Do your staff know an A from B? |publisher=National Transport Insurance |access-date=30 September 2024}}</ref> In contrast with a more common semi-trailer towing one [[trailer (vehicle)#Full trailer|trailer]] or [[semi-trailer]], the [[diesel engine|diesel]] [[tractor unit|prime mover]] of a road train hauls two or more trailers or semi-trailers. Australia has the longest and heaviest road-legal road trains in the world, weighing up to {{convert|200|t|LT ST|0}}.<ref name=definitions/>
[[File:Australian T909 Kenworth .png|thumb|B-double road train]]
'''Double''' (two-trailer) road train combinations are allowed on some roads in most states of Australia, including specified approaches to the ports and industrial areas of [[Adelaide]], [[South Australia]]<ref name="RAVnet"/> and [[Perth]], [[Western Australia]].<ref>{{cite web |url=https://www.mainroads.wa.gov.au/UsingRoads/HeavyVehicles/Pages/HeavyVehiclesHome.aspx |title=Heavy Vehicles |publisher=[[Main Roads Western Australia]] |access-date=21 October 2016 |archive-date=12 March 2018 |archive-url=https://web.archive.org/web/20180312223123/https://www.mainroads.wa.gov.au/UsingRoads/HeavyVehicles/Pages/HeavyVehiclesHome.aspx |url-status=dead }}</ref> An A-double road train should not be confused with a [[wiktionary:B-double|B-double]], which is allowed access to most of the country and in all major cities.<ref name="Hema Maps 2007">Hema Maps (Firm) & Martin, Ray. & Martin, Will. (2007), Australia truckies atlas [cartographic material] : the complete atlas for the professional driver / Hema Maps; [cartography, Ray Martin and Will Martin] – {{ISBN|978-1-86500-426-6}} {{ISBN|1-865004-26-X}} – has state by state routes and route restrictions I</ref>

In South Australia, B-triples up to {{convert|35.0|m|ftin}} and two-trailer road trains to {{convert|36.5|m|ftin}} were only permitted to travel on a small number of approved routes in the north and west of the state, including access to Adelaide's north-western suburban industrial and export areas such as [[Port Adelaide]], [[Gillman, South Australia|Gillman]] and [[Outer Harbor, South Australia|Outer Harbour]] via [[Salisbury Highway]], [[Port Wakefield Road]] and [[Augusta Highway]] before 2017.<ref name="RAVnet">{{cite map |url=http://maps.sa.gov.au/ravnet/index.html |title=RAVnet |publisher=[[Government of South Australia]] |access-date=21 October 2016}}</ref> A project named ''Improving Road Transport for the Agriculture Industry'' added {{convert|7200|km}} of key routes permitted to operate vehicles over {{cvt|30|m|ftin}} in 2015–2018.<ref>{{cite web |url=https://pir.sa.gov.au/__data/assets/pdf_file/0011/311132/Improving_Road_Transport_for_Primary_Production_Status_Update_-_web.pdf |title=IMPROVING ROAD TRANSPORT FOR PRIMARY PRODUCTION PROJECT Status update |date=February 2018 |publisher=[[Primary Industries and Regions SA]] |access-date=24 August 2019}}</ref>
[[File:Another Bloody Road Train - panoramio.jpg|thumb|Triple road train near [[Normanton, Queensland|Normanton]], Queensland]]
'''Triple''' (three-trailer) road trains operate in western [[New South Wales]], western [[Queensland]], South Australia, Western Australia and the [[Northern Territory]], with the last three states also allowing AB-quads (B double with two additional trailers coupled behind). [[Darwin, Northern Territory|Darwin]] is the only capital city in the world where triples and quads are allowed to within {{convert|1|km|mi|sigfig=2|abbr=on}} of the [[central business district]] (CBD).<ref name="Hema Maps 2007"/>

Strict regulations regarding licensing, registration, weights, and experience apply to all operators of road trains throughout Australia.

Road trains are used for transporting all manner of materials: common examples are [[livestock]], [[fuel]], mineral [[ore]]s, and general freight. Their cost-effective transport has played a significant part in the economic development of remote areas; some communities are totally reliant on regular service.
[[File:00 4591 Road train - Great Northern Highway (Western Australia).jpg|thumb|Triple road train in [[Great Northern Highway]]]]
When road trains get close to populated areas, the multiple [[#Dog-trailer_(dog_trailer)|dog-trailers]] are unhooked, the [[dolly (trailer)|dollies]] removed and then connected individually to multiple trucks at "assembly" yards.

When the flat-top trailers of a road train need to be transported empty, it is common practice to stack them. This is commonly referred to as "doubled-up" or "doubling-up". Sometimes, if many trailers are required to be moved at one time, they will be triple-stacked, or "tripled-up".

Higher Mass Limits (HML) Schemes are now in all jurisdictions in Australia, allowing trucks to carry additional weight beyond general mass limits. Some roads in some states regularly allowing up to 4 trailers at {{convert|53.5|m|ftin}} long and {{convert|136|t|LT ST}}.<ref>{{cite web |url=https://www.nhvr.gov.au/files/201707-0577-common-heavy-freight-vehicles-combinations.pdf |title=Common Heavy Freight Vehicle Configurations – NHVR |publisher=[[National Heavy Vehicle Regulator]]|access-date=24 August 2018}}</ref> On private property like mines, highway restrictions on trailer length, weight and count may not apply. Some of the heaviest road trains carrying ore are [[multiple unit]] with a diesel engine in each trailer, controlled by the tractor.<ref>{{cite web |last1=Carter |first1=Russell A. |title=Taking the Train {{!}} E & MJ |url=https://www.e-mj.com/features/taking-the-train/ |website=www.e-mj.com |date=June 2012 |quote=heavy-duty, high-capacity haulage trailer equipped with a diesel engine, cooling system, transmission and drive axle system, all controlled from the Powertrans prime mover}}</ref><ref>{{cite web |last1=Shanks |first1=Howard |title=1000 HP Kenworth C510 – Powertrailer combination Review |url=https://www.roadtrains.com.au/articles/kenworth-c510-review/ |website=Australian Roadtrains |language=en-AU |date=14 September 2017 |quote=body on the power-trans chassis .. engines rated at 450 and 500 horsepower. They are coupled to an Allison automatic transmission and tri-drive SISU hub reduction axles.}}</ref>

Diesel sales in Australia (per year) are around 32 billion litres,<ref>{{cite web |title=Australian Petroleum Statistics 2023 |url=https://www.energy.gov.au/publications/australian-petroleum-statistics-2023 |publisher=[[Department of Climate Change, Energy, the Environment and Water]] |date=December 2023 |quote=slide page 7}}</ref> of which some is used by road trains. In order to reduce emissions and running cost, trials are made with road trains powered by [[Electric vehicle battery|batteries]].<ref>{{cite web |last1=Graham |first1=James |title=World-first electric triple road train launches in SA |url=https://bigrigs.com.au/2023/04/19/world-first-electric-triple-road-train-launches-in-sa/ |website=Big Rigs |date=19 April 2023}}</ref><ref>{{cite web |title=Brisbane Truck Show uncovers huge clean transport shift, from utes to road trains – VASA |url=https://vasa.org.au/brisbane-truck-show-uncovers-huge-clean-transport-shift-from-utes-to-road-trains/ |date=24 July 2023 |quote=around 25 per cent of the 40MWh consumed so far by a Janus-converted forestry truck – while covering 18,500km with loads of up to 68.5 tonnes of timber on a 24-hour duty cycle – had been harvested from regenerative braking}}</ref><!--hydrogen road train not found-->